Mine trap-door



(No Model.)

G. J. H-ERTH & G. BON'ENBERGER. MINBTRAP DOOR.

No. 508,879. I PatentedNo-v.'14,,1893Q UNITED STATES PATENT OFFICE.-

' ordinary track.

GEORGE J. HERTl-I AND GEORGE BONENBERGER, OFEVANSVILLE, INDIANA.

MIN E. TRAP-DOOR.

SPECIFICATION forming part of Letters Patent No. 508,879, dated November 14, 1893.

Application filed July 3, 1893. Serial No. 479.453. (No model.) i

To allZ whom it may concern.-

Be it known that we, GEORGE J. HERTH and -Vanderburg and State of Indiana, have invented certainnew and useful Improvements in Mine Trap-Doors; and we do declare the fol lowing to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to .makeand use the same, reference being bad to the accompanying drawings, and to the figtires of reference marked thereon which form a part of this specification.

Our invention relates to new and useful improvements in what are known as mine trapdoorsand to one of that class which is used in mines to control or cut off air currents from different entries or rooms and the 0bject is, to provide one that will be automatic in operation, being opened and closed by any car passing through the entry on the At thesame time it is positive andsimple in action and takes but little room in the entry where the space is necessarily very limited.

Heretofore, so far as we are aware, there has been no automatic trap door used successfully in mines, those in common use being ordinary swing doors and usually attended .by a boy or man who must be constantly alert reaches it andis immediately closed on the car passing through, and it operates in precisely the same way, no matter in which direction the car approaches, and should a car reach a point near enough to the door to open it,- and for any reason be turned back, the

door would be immediately closed.

Referring to the drawings, Figure l is a perspective view ofour improved trap door and the mechanism for operating the same, the. door being closed. Fig. 2 is a similar view,

one end of the operating mechanism being broken away and the door opened.

In detail 1 represents a framework which is supported across the track in an entry of a mine the inner end 2 of such frame extending into a recess out in the wall of the tunnel for its reception, this recess being large enoughto allow the door 3 to bealso pushed back into it when opened. The door 3 has hangers on its top in which are carried wheels, these running on the horizontal bar of track 4 on the, upper cross piece of the framework 1.

5 is a shaft or rod having hearings in boxes secured to the cross ties 6 of the track 7, the shaft extending under the door and to about anequal distance on each side, and to this shaft on oneside of the door is rigidly secured an operating lover or arm 8, its upper end having pivoted to it the rods 9, which have bent ends, and are loosely connected to similar rods 10, .pivot-ed near the top of the door, one on each side, the connection between the rods 9 and 10 being springs loosely coiled around the two rods and held in place by their turned ends. The springs are shorter than the space on the rods 9 and 10 between their bent ends and this allows the-door to have a slight movement when .opening or closing independent of the operating lever 8 and serves to prevent the door from slamming or banging and makes it nearly noiseless. Y

Near the outer end of the shaft 5 on each side of the door-3 and outside of the operating lever 8, is rigidly attached a short crank 12, its outer end having pivoted thereto an arm or link 13 whose upper end is connected by a ball and socket joint to the end of a lever 14: pivoted at one side of its center to the frame 15, set at one side of the track 7, the other end of such lever having attached thereto the wire ropes 16 and 17, the first extending upward and passing over the pulley and then extending along on a line parallel I around a pulley19 mounted on an" upright or post 20; the other rope 17 extending downward from the lever 14 and passing overa pulley 2i mount-ed at thebottom of the frame 15 and then up over a pulley 22 also mounted on such frame and in a horizontal line with p the pulley 19.- .The two ropes after passing too over the pulleys 19 and 22 extend toward.

each other and are secured to opposite ends of a slotted plate 23, a swivel 24 being attached to one of the ropes to take up any slack. I

At the side of the track and in line with the slotted plate 23 is a post or upright 25 and to this or a bracket thereon is pivoted a trip arm 26 so that it will swing in a horizontal direction. This arm passes through the slot in the plate- 23 and on its outer end (which lies over the track 7 so that any pass ing car will come into contact withit and move it), is pivoted a wheel 27. On a projecting arm or bracket 28 near the top of the upright 25, is secured a coiled spring 29 whose lower end is secured to a vertical pin on the arm 26, which serves to hold the slotted plate 23 in position and prevents it from slipping back on the trip arm and thereby allowing the ropes to lose some of their movement and effect, the tendency of the spring being to draw such arm into a position at right angles to the track and so when the parts are in the position shown in- Fig. 1, where the gate is closed the arm will bear against the inner end of the slot in the plate 23, and when in the position shown in Fig. 2, will bear against the outer end of the slot, thus being always in a position to move the operating mechanism as soon as the outer end of the arm 26 comes in contact with a pass.- ing car.

Having described ourdevice in detail,we will proceed with the operation which is as follows: The parts being in the position shown in Fig. l and the door closed, upon a car striking one of the trip arms 26 while going toward the trap-door, the arm will be swung around toward the door, moving with it the slotted plate 23 in the same direction and drawing the rope 16 over the pulleys 18 and 19 and thereby lifting the end of the lever 14, de-

pressing its opposite end and forcing downward the link 13 and the end of the crank 12, turning the rod or shaft 5, and swinging the operating lever S inward and with it the trap-door 3, carrying the same back into the re cess formed in the side of the entry, and leavingthe track clear for the car to pass through. After passing by the door the car will strike the other trip arm 26 which is now turnedinward swinging it out and thereby moving the slotted plate 23 in the same direction, and drawing the rope 17, will pull the end of the lever 14 down and through the link 13 and crank 12, turn the shaft 5 and swing the operating lever 8 outward, closing the door hehind the car. It will thus be seen that the operation of our door is simple and positive and there can be no chance of its being left open. By the arrangement of the spring connection of the lever 8 with the door 3, there is little or no noise in opening and shutting the same, and the lever being connected at the top of the door its weight will hold it either open or shut till the mechanism be operated to open or shut it as the case may be.

In practice there will seldom be any necessity of having the different frames to which the mechanism is shown attached as it can be attached in most cases to the roof supports and braces usually found in all parts of mines.

The mechanism may be set to be operated by a car at any desired distance from the door by merely changing the position of the trip arm 26 and its support, and also the outer pulley 19. V

Instead of using a spring 29 for drawing the trip arm against the ends of the slot in the plate 23, we can use with equally as good, if not better results, a weight secured to the end of a rope passing through a staple secured to the trip arm, the upper end of the rope being secured to the bracket 28, as is the spring, this modification being shown in Fig. 2. So that a miner or other person can get through the door when desired, a hole or opening is made near the outer end of the same and a block covers such opening on one side so that the block serves a handle on that side and the opening the same purpose on the other side.

We do not wish to limit ourselves to the precise construction herein shown and de- 9 scribed as many modifications might be made which would not change the operation of our device and would not be a departure from the spirit of our invention; but

What we claim, and desire to secure by Letters Patent of the United States, is-- 1. A sliding trap-door adapted to open and shut across an entry and the track therein, an operating lever mounted on a shaft below, its upper end having pivoted thereto on each side a rod, similar rods pivoted to the door and connected to the first by springs and mechanism for turning the shaft of such lever in either direction, substantially as set forth.

2. A mine trap-door adapted to be opened and shut across an entry and track by an operating lever mounted on a shaft below, cranks on such shaft on each side of the door and arms connecting such cranks with pivoted levers, a trip arm pivoted in the tunnel on each side of the door, each of such working through a slotted plate carried on a rope running over pulleys and connected with the pivoted levers for turning the shaft, such trip arm adapted to contact with passing cars, whereby through its connections the door is first opened and then shut, substantially as set forth.

In testimony whereof we affix our-signatures in presence of two witnesses.

GEORGE J. HERTH.

- GEORGE BONENBERGER.

Witnesses:

EMIL W. SAUPERT, GEORGE SoHwINN.

IOC 

